During the century following the crucifixion of Christ, the apostles charged with spreading the “good news” of the Gospels enjoyed rather limited success. In an historical “blink of the eye” – during the late second and third century c.e. – people throughout a collapsing Roman Empire embraced Christianity. During the fourth century Christianity became the official religion of the Empire, and by the sixth century c.e., most Europeans – numbering in the millions – understood themselves as Christian.

Christianity experienced a similar history some 1,400 years later in Latin America. Here, too, the collapse of empires (e.g., Mexica, Inca) ushered in a period of several centuries, during which millions of Indians came to understand themselves as Christian.

This book is a comparative study of early Christianity in the late Roman Empire (c. 150–800 c.e.) and in colonial Mexico (c. 1520–1720 c.e.). Following the early success of Mendicant missionaries in southern Mexico, the Jesuits, between 1591 and 1650, baptized over four hundred thousand Indians and established a vast network of Christian communities in northern Mexico. My central thesis is that the Mendicant and especially the Jesuit enterprise, although not on the same temporal or spatial scale as the rise of Christianity in Europe, nevertheless entailed similar processes. Perhaps most significant, the Christianization of pagan Europe and Indian Mexico was coincident with epidemics of acute and chronic infectious disease that undermined the structure and functioning of pagan and Indian societies, respectively.